Display panel or portion thereof with a graphical user interface



FIG. 1 is a front view of a display panel or portion thereof with a graphical user interface, showing a first embodiment of the new design; and,

FIG. 2 is a front view of second embodiment thereof.

The subject matter of the present disclosure includes graphical user interface components present. The broken lines depicting a display panel or portion thereof illustrate the article of manufacture and form no part of the claimed design. 

CLAIM The ornamental design for display panel or portion thereof with a graphical user interface, as shown and described. 